What is a Form CRS?
Form CRS, short for Customer or Client Relationship Summary, is a brief disclosure document that SEC-registered investment advisers and broker-dealers must give to retail investors before or when they begin a brokerage or advisory relationship. It lays out, in plain language, the services a firm offers, what those services cost, the conflicts of interest involved, the firm's disciplinary history, and where to get more information. The form grew out of the 
SEC's 2019 rulemaking package that also created Regulation Best Interest, and it is meant to help everyday investors understand and compare firms before they hand over money. It supplements rather than replaces the fuller disclosure documents firms already file, such as Form ADV. Investors can look up a specific firm's relationship summary directly through 
Investor.gov.
What the document must cover
Every relationship summary has to address four standard topics: the relationships and services the firm provides; its fees, costs, conflicts of interest, and standard of conduct; whether the firm or its people have a reportable disciplinary history; and where investors can find additional information. The document must be written in plain English, generally limited to two pages, or up to four pages for a firm that is dual-registered as both a broker-dealer and an investment adviser and files a single combined summary. Firms are also required to include "conversation starter" questions that investors can put directly to the firm, covering topics like fees, conflicts, and whether the person providing the advice has ever had a legal or disciplinary event, as described on Investor.gov's Form CRS page. The consistent structure and headings are deliberate, so that a person shopping between a broker and an adviser, or between two competing firms, can compare like against like.
Why brokers and advisers are treated differently
Brokers and investment advisers operate under different business models, and Form CRS is built to surface that difference rather than paper over it. Investor.gov explains that brokers generally provide transaction-based services such as executing trades and making one-time recommendations, and typically charge commissions or markups per transaction. Investment advisers, by contrast, generally provide ongoing advice, account monitoring, and sometimes discretionary management of a client's money, usually for an asset-based fee charged on a recurring basis. Firms that are dual registrants offer both types of services, so their relationship summary has to make clear which capacity applies to a given account or recommendation. Because the compensation structures and duties differ, the relationship summary is one of the few places an investor can see the distinction laid out side by side in a firm's own words.
When and how a firm has to deliver it
A firm must deliver its relationship summary before or at the point of specific triggering events: signing an advisory contract, receiving a brokerage recommendation, placing an order, or opening an account, according to the SEC's small business compliance guide. Existing clients also have to receive an updated copy when they open a new account or service, when a firm recommends a rollover, when the document is updated, or within thirty days of asking for one. If a summary becomes materially inaccurate, the firm has thirty days to file a corrected version and must communicate the changes to existing clients within sixty days. The current version has to be posted prominently on the firm's public website if it has one. Investment advisers file their relationship summary as Form ADV Part 3 through the Investment Adviser Registration Depository, while broker-dealers file Form CRS through Web CRD, and dual registrants use both systems as applicable.
Checking a firm's relationship summary
Any investor can pull up a specific firm's current relationship summary before deciding whether to work with it. Investor.gov directs users to its Check Out Your Investment Professional tool, where searching by firm or individual name and selecting "Get Details" followed by "Relationship Summary" brings up the document on file. That same lookup shows whether a firm or individual has "Disclosure Reported," an indicator of disciplinary history, with more detail available in a broker's disclosures or an adviser's Form ADV Part 2 brochure. Someone who has a problem with an investment firm can also file a complaint using the SEC's investor complaint form, or send general questions through the SEC's investor question form. Reviewing the relationship summary before opening an account, and asking the firm its own "conversation starter" questions directly, is the concrete next step for anyone comparing brokers or advisers.